EN 10025 Steel Grades for Singapore Projects — S275, S355 vs SS304, SS316
A short narrative orientation to the four steel grades that show up on most Singapore drawings. The full technical reference — comparison table, fabrication notes and the downloadable workbook — now lives on the EN 10025 steel grades comparison page under our Glass & Metal service.
Open almost any Singapore structural drawing and you will see one of four steel grades stamped on the section: S275 or S355 for mild steel, or SS304 (1.4301) and SS316 (1.4401) for stainless. The choice between them drives the price per kilogram, the maintenance schedule and the corrosion lifetime of every weld and anchor on the job. This blog post is a short narrative orientation; the canonical fabricator-side reference is the EN 10025 steel grades comparison page.
The four grades, in one paragraph
S275 and S355 are mild steel to EN 10025-2. Both rust if left bare, so under Singapore's humid, salt-laden coastal air they are nearly always painted to ISO 12944 or hot-dip galvanised per ISO 1461. S275 is the cheaper, lower-strength workhorse — brackets, secondary beams, walkways, small platforms. S355 is the default for primary frames, columns, trusses and long-span beams because its higher yield (355 MPa vs 275 MPa) lets the engineer span further with a lighter section. SS304 and SS316 are austenitic stainless steels to EN 10088-2, and they never need painting. SS304 suits indoor or sheltered handrails, balustrades and architectural fittings. SS316 adds about 2 % molybdenum, which resists chloride pitting — the right choice for coastal projects, splash zones and any 25-year-life component facing the sea.
The selection rule of thumb: mild steel for strength and budget, galvanised mild steel for outdoor durability, SS304 for indoor finish, SS316 for coastal exposure. Match the grade to the environment first, the load case second and the budget third.
Where the rest of this article went
The detailed property table, coating and welding notes, fabrication-side decision tree and the downloadable 49-sheet comparison workbook are now on the canonical metal-section page:
→ EN 10025 steel grades comparison — Singapore fabrication reference
That page is structured around the workshop questions our fabricators answer every week — where the steel will live, what the design driver is, whether the surface is part of the architecture, and what the inspection / certification regime looks like. It also links the EN10025_Steel_Grades_Comparison.xlsx workbook (section catalogues, weight and cost calculators, Fischer anchor capacity tables) used in our own shop.
Related Ezzogenics technical articles
- Handrail design — SS304 vs mild steel comparative strength and suitability
- Galvanised mild steel, SS304 and SS316 lifespan in tropical exposure
- Cat ladders for Singapore buildings — aluminium, SS304 or galvanised mild steel?
- Wall anchor specification — Hilti vs Fischer, cracked vs uncracked, bolt sizing
For Ezzogenics fabrication enquiries — handrails, cat ladders, balustrades, gates and architectural metalwork — see the Glass & Metal and Work at Height service pages, or contact us with the drawing and specification.